Studies Explore Reasons for 'Fade-Out' Effect

What makes learning gains vanish?

It can take years of effort for educators and researchers to identify an intervention that really, truly improves student achievement, so it's a source of universal frustration that even the strongest, most promising effects tend to vanish after a few years.

That's why a new wave of research projects are trying to understand what causes fade-out in education programs, to rethink how educators evaluate the staying power of a program's benefits, and to identify the types of interventions that may have long-lasting effects for children.

Among those efforts, the Institute of Education Sciences last week announced more than $26 million in grants to create a network of teams around the country focused on finding ways to stop preschool benefits from fading over the elementary grades.

"We believe these networks will lead to important advances in early-childhood education," said Thomas Brock, the commissioner of the National Center for Education Research, which is part of the IES. "The idea is for the network teams to develop a deeper understanding of problems and solutions surrounding the issue, and then share what they have learned with policymakers and practitioners to improve teaching and learning for all students."

Cognitive Impacts in Early-Childhood Education

In a forthcoming analysis of 67 early-childhood-education programs found to have significant benefits, researchers at the University of California, Irvine, and Duke University found that most results faded within a few years.

It makes sense to start with early-childhood education, which has proven particularly nettlesome for educators when it comes to holding onto immediate gains. Studies of the federal Head Start program, Tennessee's voluntary prekindergarten, and even the famous Perry Preschool Project all showed significant early academic gains for students that regressed as children moved through elementary school. Perry Preschool's academic gains dropped by more than half from age 5, shortly after students left the program, to age 8.

The Long View

Two comprehensive and highly regarded early-childhood education programs, the Perry Preschool Project in the 1960s and the Abecedarian Program in North Carolina in the 1970s, each followed their students for decades—long enough for so-called "sleeper" benefits to emerge, such as higher high school graduation rates and lower adult crime rates for participants. But it remains difficult to find the path through the fading early results to the later benefits.

"It's really nice that Abecedarian and Perry showed these later-emerging effects on life outcomes, but we don't have a great understanding of why," said Drew Bailey, an assistant education professor studying fade-out at the University of California, Irvine. "Was it because students knew more math, or their personalities changed, or Perry reduced some risks and improved opportunities at a critical time in their development? It's probably some combination of all that."

If there was a "CSI: Education," researchers like Bailey and John Protzko would be the ones dusting the body for fingerprints and lining up ballistics trajectories.

In two separate studies, the researchers and their colleagues are piecing together narratives of what happened to more than 100 studies' worth of promising education programs which showed benefits that faltered and faded over the years.

Comparing 'Trajectories'

"One problem is people don't look at the trajectories of treatment and control groups separately; they just look at the difference between them," Bailey said. "If the treatment is fading out because the treatment group is getting worse, that means something quite different than if the control group is catching up."

Best Bets for Lasting Improvement

Researchers at the University of California, Irvine, and Duke University are developing a framework to identify the targets for educational interventions that could lead to strong, sustained improvements for students.
The most promising targets aim to improve skills, beliefs, and behaviors in the sweet spot of three kinds of critical areas, those that are:

In a 2015 meta-analysis in the journal Intelligence, Protzko, a postdoctoral scholar in cognitive science at the University of California, Santa Barbara, analyzed data on nearly 7,600 participants in 39 randomized controlled trials of programs designed to improve students' intelligence. The programs included educational interventions, like preschool and summer school, and nonacademic programs like nutritional supplements for pregnant women. In particular, Protzko looked at how students fared after participating in a program that had been shown to statistically, significantly improve intelligence immediately after the program ended.

Over time, the benefits of each program faded, regardless of how long or intense it was initially. Moreover, interventions that started earlier in a child's life "were no more effective and lasted no longer" than those begun later, Protzko found.

After analyzing the patterns of fading results, Protzko suggested that most gains in IQ fade within a year or two because the students who saw results from the intervention adapted to less-enriched academic environments.

"It's easy to think of this in terms of loss—you raised intelligence, and now these kids have lost it," Protzko said. "But adaptation is a better way to think about it. When you remove the more challenging environment [of the intervention], the students adapt to the level of cognitive challenge they have."

Nearly all of the students in the experiments that Protzko studied were from low-income backgrounds, and he noted that it's impossible to tell whether they did not look for or simply could not find ways to continue to challenge themselves after the intervention was over. Either way, their gains seemed to shrink over time, like the muscles of a runner who trained for a marathon and then stopped running.

Bailey and colleagues at UC-Irvine and Duke University suggested interventions must be seen as pieces in the ongoing process of education rather than attempts to create silver bullets.

They analyzed 67 early-childhood intervention programs that showed significant cognitive effects for students between 1960 and 2007. (Several of these overlapped with those that Protzko studied.) Like Protzko, they found that those gains dropped by half in the first 12 months following the interventions, and declined by half again in the next year or two, becoming insignificant.

Unlike Protzko, however, the researchers from UC-Irvine and Duke suggest that the students who participated in the intervention continued to learn at the same rate in the years that followed, as the control-group students caught up.

• They must be malleable, or capable of being changed by the educator or school. For example, the researchers noted that "conscientiousness" as a personality trait has been closely associated with students' school grades and later job performance, but it has proven very stable over a person's life.

• They must be fundamental to a long-term goal. For example, prepping for an end-of-year test might boost performance on that test, but generally does not contribute to a student's long-term academic skills.

• They must not be something that students would develop on their own.

That last criterion trips up many promising interventions. For example, in a 2013 study in Perspectives in Psychological Science on early-childhood programs, Protzko found that interventions that taught parents to engage with their children while reading together raised young children's IQ by more than 6 points, but did not affect children older than 4. That finding suggested the programs accelerated normal language development.

Bailey's co-author, Gregory Duncan, a distinguished education professor at UC-Irvine, said educators may be able to give sustained benefits by targeting students in extremely deprived environments, such as supporting emotional self-regulation for teenagers in violent neighborhoods or households.

Educators can also take advantage of times when a short-term benefit may be all that's needed to make a difference. For example, the H&R Block Project found providing low-income families with help applying for college financial aid during normal tax-filing sessions significantly raised the share of poor students enrolling in college.

"It's all about being in the right place at the right time with the right kind of intervention to prevent bad things from happening to kids," Duncan said.

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